can any one who is an electrician please help (UK preferably)?

Question

I have just removed an old ceiling rose and replaced it with a brand new one BUT now my lights don't work unless there's a bulb in the one I've just replaced. HOWEVER the one I've replaced won't turn on BUT when I turn a different light switch it illuminates but doesn't turn on properly! can you help please???

Answer 1

Ha Ha Ha... I've been called to this so any times... it's because you failed to note which pair of wires go to the switch... you see you have three terminals, not including the earth, one for neutrals, one for lives, and one for switched live....

you have to identify the pair that go to the switch... think of one of this pair as live, the other as switched live... regardless of their colour. the live goes to the live (red or Brown) terminal strip, the switched live to one side of the bulb. the other side of the bulb goes to neutral along with all the blacks (blues in new colours)

It's not easy to describe, dead easy to do....

Answer 2

O.K, you're light circuits are on a 'loop circuit' meaning that the wire supplying electricity to your (now broken) light feeds another one and so on until it loops back round to complete the circuit.

What you have failed to do is to distinguish which wire is the switch (these are usually red(the same colour as the looping wires) and it's an easy mistake to make, fortunately it's easy to rectify aswell.

Get a multimeter set it to buzz when the two terminals are touched together and then connect one end to the light switch feed and just touch each of the wires in turn when the multimeter buzzes you have your baby, if it doesn't at all, try the balck wires as on older houses occassionally there is a black wire which feeds from a red wire. Once you have got it mark it with tippex and re-connect the rose up with the switch feed connecting to the brown wire from the ceiling rose, the remaining reds in the middle (or loop) if it is marked and the black wires to the blue on the ceiling rose. Everything should then work fine.

Answer 3

You may have either 2 cables (red/Black/Earth) or 3 cables.
If you have 2 cables, its a 'Spur', if you have 3, then its a 'Ring' circuit.
In either case, put the power off, then using a continuity tester, check each Red/Black pair, to identify the Switch cable.
Put your tester across the pair, get someone to switch on/off on the light switch, you will soon know.
If you have not got a continuity tester, either get a small meter from a DIY store (generally they can check mains as well)
Look at your new ceiling rose carefully, you will note that some of the blocks are '3way common' (3 holes/screws to common bar), others are 2 way.each of the blocks will be isolated.
The good practice is to 'Switch the live'
In the case of the 'Spur', put the mains wire black (not the switch wire black) into one of the common blocks, and the lamp wire black into the same block. Then, take the mains wire red put it into another common block, and the switch wire red into the same block. Take the switch wire black and put it into another common block, this is known as the 'Switched Live', it will only be live when the switch is on, connect the lamp wire red and put it into the same block as the switch wire black.
In the case of 'Ring' circuit, take the rose, connect the two 'non switch' blacks into a 3 way block, and connect the lamp wire black into the same block. Now take the 2 'non switch' reds, into another 3 way block, and the 'Switch cable' red into the same block. You should at this time have the 'switch cable' black and the lamp wire red left. Connect these into another 2 way block, this is the switched live as before.
Ensure in either case that your earths (the bare wire on each cable) are sheathed with Green/Yellow sleeve, connected to thier own block, and continued to the light fitting.
Make sure all your screws are tight!!!!

Answer 4

I just did a mate's lights as he'd blown umpteen fuses & got black streaks up the wall when putting in some new lighting....idiot.

Took me 10 mins to fix.....but whoever wired the house originally did it VERY wrong - permanent LIVE at rose, switched on neutral.

Be VERY careful, sometimes the original wiring may be incorrect, if you are unsure - get a qualified electrician or VERY competent DIYer to take a look.

This is why I wont offer ANY advice as to how it is or was wired - only a physical inspection can do that. Be VERY wary of taking wiring adivice from these comments.

Answer 5

the switch wire can fool you because the black and red wires are both live. You could try to find this wire by turning the switch to the off position then you should be able to find this wire with a tester.
You may need a juction box to sort this out and fixed above the ceiling!
Hope this helps,

Answer 6

yea. you have done it wrong. for a start all your reds want to be in the middle part of the rose, all the black ones want to go into the neutral connection apart from the black with trhe red tape on it,

it wants to be connected to the brown"live" of the bulb

and the blue "neutral" wants to connect to the group of blacks

the "old celing rose comment does not apply, to make your lights do what they are doing you would HAVE to be operating on a loop in system so you will have 3 terminals + earth.. i thank you

Answer 7

an old ceiling rose has only 2 terminals make sure all your neutrals are connected

Answer 8

Can't really help but try www.screwfix.com and click on the talk forum.There are forums for all trades electrical/plumbing/building etc..
You will need to register,but the help is quite good ..I've used it many a times for help.
Good luck

Answer 9

You have connected the new rose incorrectly......take it apart and try again....or pay someone how knows what they are doing to do it for you..... should only take him 10 mins!

Answer 10

Try finding an electrician from

http://www.niceic.org.uk/common/contractor_search.html